Robotically loaded epitaxial deposition apparatus

Abstract

A susceptor carrying semiconductor wafers for processing is suspended from a compliant attachment at its upper end and is lowered into a reaction chamber for processing. At the completion of processing, the susceptor is withdrawn vertically to permit a robot to unload the processed wafers and load unprocessed wafers. In order to fix the position of the susceptor during the loading operations, a support carriage is moved into position to engage the lower end of the susceptor. Noxious and corrosive chloride vapors are simultaneously withdrawn from the reaction chamber by a vacuum line attached to the support carriage.

We claim: 
     
       1. In a semiconductor-processing apparatus of the type employing a reaction chamber for confining a reactive gaseous atmosphere in contact with a substrate, the combination comprising: a susceptor for supporting said substrate;   susceptor mounting means for supporting said susceptor within said apparatus;   substrate loading means selectively operable to: (1) load a substrate onto said susceptor for processing within said apparatus, and (2) remove a substrate from said susceptor at the completion of said processing;   susceptor stabilization means mounted on said apparatus and selectively operable independently of said loading means to: (1) move into engagement with said susceptor for fixing the position of said susceptor with respect to said apparatus during the operations of loading and removing a substrate, and (2) move out of engagement with said susceptor and (3) produce a vacuum in a region adjacent said chamber opening.   
     
     
       2. The apparatus of claim 1 wherein: said susceptor mounting means suspends said susceptor within said apparatus at an upper support point on said susceptor; and,   said susceptor stabilization means selectively engages said susceptor at a point thereon removed from said upper support point.   
     
     
       3. The apparatus of claim 1 wherein said susceptor stabilization means includes means to frictionally engage the lower end of said susceptor. 
     
     
       4. The apparatus of claim 1 further comprising indicator means coupled to said susceptor stabilization means for supplying an indication of disengagement of said susceptor stabilization means from said susceptor. 
     
     
       5. The apparatus of claim 1 wherein said susceptor stabilization means comprises: a contactor means to engage said susceptor when brought into contact therewith;   a transport means for selectively moving said contactor means: (1) toward, and into engagement with, said susceptor, and (2) away from said susceptor.   
     
     
       6. The apparatus of claim 5 wherein said transport means comprises: first movement means for moving said contactor means toward or away from said susceptor along a first path of motion lying generally in a first plane;   second movement means for moving said contactor means toward or away from said susceptor along a second path of motion lying generally in a second plane which intersects said first plane;   said first and second movement means being selectively operable: (1) to move said contactor means toward said susceptor along said first and second paths of motion to a contact position in which said contactor engages said susceptor, and (2) to move said contactor means away from said susceptor along said first and second paths of motion to a rest position in which said susceptor stabilization means is removed from said susceptor.   
     
     
       7. In a semiconductor-processing apparatus of the type employing a reaction chamber for confining a reactive gaseous atmosphere in contact with a substrate, the combination comprising: a susceptor for supporting said substrate;   susceptor mounting means for supporting said susceptor within said apparatus;   substrate loading means selectively operable to: (1) load a substrate onto said susceptor for processing within said apparatus, and (2) remove a substrate from said susceptor at the completion of said processing;   susceptor stabilization means mounted on said apparatus and selectively operable independently of said loading means to: (1) move into engagement with said susceptor for fixing the position of said susceptor with respect to said apparatus during the operations of loading and removing a substrate, and (2) move out of engagement with said susceptor;   a reaction chamber having a closable opening through which said susceptor can be inserted and removed from said chamber;   chamber loading means for causing relative motion between said chamber and susceptor along a chamber loading axis between a closed position in which said susceptor is confined within said chamber during substrate processing, and an open position in which said susceptor is withdrawn from said chamber through said chamber opening to permit removal of a processed substrate and loading of an unprocessed substrate; and   said susceptor stabilization means comprising chamber exhaust means for producing a vacuum in a region adjacent said chamber opening for withdrawing noxious process-byproduct vapors from said chamber when said closable opening is open.   
     
     
       8. The apparatus of claim 7 wherein said susceptor stabilization means comprises: a contactor means to engage said susceptor when brought into contact therewith;   a transport means for selectively moving said contactor means: (1) toward, and into engagement with, said susceptor, and (2) away from said susceptor.   
     
     
       9. The apparatus of claim 7 further comprising: a carriage selectively movable along a first path of motion generally transverse to said chamber loading axis, said path of motion extending from a position adjacent said chamber opening to a position removed from said chamber opening; said carriage being further selectively movable along a second path of motion extending generally in a direction from said chamber opening to said susceptor when said chamber and susceptor are in said open position; and,   a contactor means positioned on said carriage and disposed facing said susceptor for engaging and fixedly supporting said susceptor when brought into contact therewith.   
     
     
       10. The apparatus of claim 9 further comprising: a vacuum duct coupled to said carriage for movement therewith, said vacuum duct having an opening adjacent a portion of said carriage facing said chamber loading axis, and extending therefrom to a location remote from said chamber axis for connection to a source of vacuum.   
     
     
       11. The apparatus of claim 9 further comprising indicator means coupled to said carriage for supplying an indication of disengagement of said susceptor stabilization means from said susceptor.